Extract canvas live stroke, node canvas state, and preset panel UI

docs/modernization/roadmap.md

@@ -79,14 +79,14 @@ What is still carrying too much live ownership:
 
 Current hotspot files:
 
-- `src/canvas.cpp`: 2122 lines
+- `src/canvas.cpp`: 1490 lines
 - `src/app_layout.cpp`: 125 lines
 - `src/canvas_modes.cpp`: 1014 lines
 - `src/node.cpp`: 995 lines
 - `src/main.cpp`: 271 lines
-- `src/node_panel_brush.cpp`: 652 lines
+- `src/node_panel_brush.cpp`: 435 lines
 - `src/node_stroke_preview.cpp`: 751 lines
-- `src/node_canvas.cpp`: 877 lines
+- `src/node_canvas.cpp`: 702 lines
 - `src/app.cpp`: 575 lines
 - `src/app_dialogs.cpp`: 168 lines
 
@@ -260,7 +260,11 @@ Current architecture mismatches that must be treated as real blockers:
   larger stroke commit/sample execution family now also route through
   `src/legacy_canvas_stroke_commit_services.*` instead of staying inline in
   `src/canvas.cpp`, which trims another large retained stroke-render and
-  viewport-state execution family from the live canvas shell, while the
+  viewport-state execution family from the live canvas shell, while the live
+  `Canvas::stroke_draw()` orchestration now also routes through
+  `src/legacy_canvas_stroke_live_services.cpp` instead of staying inline in
+  `src/canvas.cpp`, which materially thins another large retained live
+  stroke-render pocket, while the
   `CanvasModeTransform` interaction family now also routes through
   `src/legacy_canvas_mode_transform.cpp` instead of staying inline in
   `src/canvas_modes.cpp`, which materially thins another retained canvas-view
@@ -273,10 +277,19 @@ Current architecture mismatches that must be treated as real blockers:
   import/export/import-ABR routing now also lives in
   `src/legacy_brush_preset_services.*` instead of staying inline in
   `src/node_panel_brush.cpp`, which trims another large preset-workflow pocket
-  from the live UI node, while `NodeCanvas::handle_event()` now also routes
+  from the live UI node, while `NodePanelBrushPreset` init/menu wiring, click
+  handling, item construction, and added-state update now also route through
+  `src/legacy_brush_preset_panel_ui.*` instead of staying inline in
+  `src/node_panel_brush.cpp`, which materially thins another retained preset
+  panel UI pocket, while `NodeCanvas::handle_event()` now also routes
   through `execute_node_canvas_handle_event(...)`, which trims another coherent
   input-routing block from `src/node_canvas.cpp` even though the file is still
-  a live canvas/controller shell, while shared canvas-mode GL wrappers plus the
+  a live canvas/controller shell, while `NodeCanvas` restore/clear context,
+  resize handling, camera reset, buffer creation, cursor visibility/update,
+  tick, and destroy ownership now also route through
+  `src/legacy_node_canvas_state_services.*` instead of staying inline in
+  `src/node_canvas.cpp`, which materially thins another retained state/control
+  pocket, while shared canvas-mode GL wrappers plus the
   `CanvasModeBasicCamera` and `CanvasModeCamera` input handlers now also route
   through `src/legacy_canvas_mode_helpers.*` instead of staying inline in
   `src/canvas_modes.cpp`, while

docs/modernization/tasks.md

@@ -91,7 +91,7 @@ Status: In Progress
 
 Why now:
 `src/canvas.cpp` is still the biggest single architectural blocker at about
-2122 lines, with `src/canvas_modes.cpp` still large at about 1014 lines.
+1490 lines, with `src/canvas_modes.cpp` still large at about 1014 lines.
 
 Current slice:
 - Canvas state-management helpers for picking, clear/clear-all, layer
@@ -126,6 +126,10 @@ Current slice:
   `src/legacy_canvas_mode_transform.cpp` instead of staying inline in
   `src/canvas_modes.cpp`, which materially thins another retained
   transform-mode pocket from the broader canvas/render hotspot family.
+- The live `Canvas::stroke_draw()` orchestration now also lives in
+  `src/legacy_canvas_stroke_live_services.cpp` instead of staying inline in
+  `src/canvas.cpp`, which materially thins another large retained live
+  stroke-render pocket from the canvas shell.
 
 Write scope:
 - `src/canvas.cpp`
@@ -289,6 +293,11 @@ Current slice:
   `execute_node_canvas_handle_event(...)` helper, which trims another coherent
   input-routing block from `src/node_canvas.cpp` even though the node still
   owns broader canvas/controller behavior.
+- `NodeCanvas` restore/clear context, resize handling, camera reset, buffer
+  creation, cursor visibility/update, tick, and destroy ownership now also
+  live in `src/legacy_node_canvas_state_services.*` instead of staying inline
+  in `src/node_canvas.cpp`, which materially thins another retained
+  state/control pocket without reopening the draw path.
 
 Write scope:
 - `src/node_stroke_preview.cpp`
@@ -1011,6 +1020,12 @@ Current slice:
   in `src/node_panel_brush.cpp`, which trims another large preset-workflow
   pocket from the live UI node even though the broader cloud/package worker
   split still remains follow-up work.
+- `NodePanelBrushPreset` init/menu wiring, click handling, item construction,
+  and added-state update now also live in
+  `src/legacy_brush_preset_panel_ui.*` instead of staying inline in
+  `src/node_panel_brush.cpp`, which materially thins another retained preset
+  panel UI pocket even though cloud/package worker ownership remains the
+  follow-up.
 
 Write scope:
 - `src/legacy_cloud_services.*`